Jerabek

Jerabek Hyperbola

Given a triangle t, the isogonal-conjugate images of lines are conics passing through the vertices of t.
The Jerabek hyperbola is the isogonal-conjugate image of the Euler line. It is a rectangular hyperbola, passing through the orthocenter and the circumcenter and many other interesting points of the triangle.

X and X' are isogonal conjugates. X is free movable on the Euler line, through the tool [Select on Contour] (Ctrl+2). For another interesting conic, related to the triangle look at Kiepert.html .

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